1. Field of the Invention
The present invention relates to an IC (integrated circuit) card wrong insertion preventing mechanism and an IC card connector incorporating the mechanism in a multiple card accommodation portion thereof.
2. Description of the Related Art
In general, the functions of electronic apparatus are expanded in various ways by mounting IC cards such as MMCs (multimedia cards (trademark)), SD (secure digital) cards, and MINI SD CARDs (trademark) in the apparatus through IC card connectors.
In order to allow a plurality of IC cards having different shapes to be mounted and used in a single electronic apparatus, for example, as shown in Japanese Patent Application Laid-open Nos. 2004-311416 and 2004-193111, a proposed IC card connectors are provided with a multiple card accommodation portion which has a common card slot to be commonly used for such IC cards and to and from which the IC cards are selectively mounded and removed one at a time.
In such an IC card connector having a multiple card accommodation portion, each card accommodation portions are formed in tiers while extending along the IC card mounting and removing direction such that they partially overlap each other. Groups of contact terminals associated with contact pads of respective IC cards are separately provided in the card accommodation portions.
In such a configuration, it is required to prevent a user from inserting a predetermined IC card into a card accommodation portion different from the correct card accommodation portion by mistake, and inserting operations must be performed such that an IC card can be smoothly mounted and removed while avoiding damage to contact terminals which are not used by the IC card.
According to some proposals on measures to satisfy such requirements, for example, as disclosed in Japanese Patent Application Laid-open Nos. 2004-311416 and 2004-193111, a wrong insertion preventing mechanism is provided in the neighborhood of a common card slot in a connector, the mechanism including a wrong insertion restraining member for restraining the insertion of a predetermined IC card into a wrong card accommodation portion.
For example, the wrong insertion preventing mechanism comprises a wrong insertion restraining member for restraining wrong insertion of a second IC card having a relatively small transverse width compared to a first IC card into a card accommodation portion for the first IC card, a lock/unlock mechanism for taking the wrong insertion restraining member in a first state (locked state) for restraining the insertion of the second IC card and a second state (unlocked state) to allow insertion of the first IC card having a relatively wide transverse width, and an urging member for urging the wrong insertion restraining member in the direction opposite to the card inserting direction.
The wrong insertion restraining member is provided substantially orthogonally to the direction in which the IC cards are mounted and removed such that it extends across an end of a card accommodation portion on the side of a card slot. A narrow opening allowing the first IC card to pass through is formed under the wrong insertion restraining member. Both ends of the wrong insertion restraining member are movably supported at the periphery of the card accommodation portion and configured such that they can be selectively engaged with engaging portions of locking members of the above-described lock/unlock mechanism. The engaging portions of the locking members can be elastically displaced.
In such a configuration, the wrong insertion restraining member is locked in the above-described first state when both ends of the same are engaged with the respective engaging portions of the locking member. More specifically, the insertion of the second IC card into the card accommodation portion of the first IC card is restrained by the wrong insertion restraining member that is in the locked state. The second IC card is mounted in a predetermined card accommodation portion through the narrow opening under the wrong insertion restraining member.
On the one hand, when the first IC card is mounted, the locking members are pressed by respective side parts of the inserted IC card immediately after the leading end of the IC card passes through the card slot, whereby both ends of the wrong insertion restraining member are disengaged from the engaging portions of the respective locking members.
Hereby, the wrong insertion restraining member is consequently unlocked from the locked state. When the IC card is further pushed in the card accommodation portion against the urging force of the above-described urging member, for example, the wrong insertion restraining member is moved to be retracted from the passage of the IC card, and the first IC card passes over the wrong insertion restraining member to be mounted in the card accommodation portion for the first IC card.
In the case of an IC card connector having a wrong insertion preventing mechanism as described above, when a user sets each IC card with the end of the card having no contact pad facing in the forward direction and erroneously inserts the card into a card accommodation portion from that end, so-called inverted insertion of an IC card might occur.
In such a case, when the first IC card is inserted in such a manner as the inverted insertion, since the end of the first IC card cannot be mounted on an eject mechanism provided in the card accommodation portion, further insertion of the card into the card accommodation portion is prevented even if the wrong insertion restraining member is unlocked from the locked state by the lock/unlock mechanism.
However, when the second IC card is inserted in such a manner as the inverted insertion, one of the locking members is pressed by one side part of the second IC card to disengage one end of the wrong insertion restraining member from the engaging portion of the locking member. When the wrong insertion restraining member is moved further by being pressed by the end of the second IC card, the urging force of the above-described urging member may be balanced with a restoring force of the locking member, and the end of the wrong insertion restraining member may consequently be kept in the unlocked state.
In such a case, the other locking member is subsequently pressed by the other side part of the second IC card in the same manner. Then, when the wrong insertion restraining member is further moved by being pressed by the end of the second IC card, both ends of the wrong insertion restraining member become unlocked. As a result, the first IC card may be inserted in the inverted insertion state by mistake, which can result in damage to contact terminals.